How are Monthly Means Calculated?

The table shows values for the selected month from each year in the
database. Values are given in degrees Celsius. Averages shown here
are calculated from daily averages for the month. The value in parentheses
following the monthly mean value is the standard deviation of the daily
averages used to compute the mean. The minimum (maximum) is the average of
the minimum (maximum) temperature observed on each day of the selected month.
Table rows are shown by default in descending order of Mean value. Click on the
column heads to change the ordering. In some cases the months may be incomplete.
Months that have fewer than 24 daily values are shown in red. This may include
the present month.

The last row in the table gives the averages of the columns. Click through
the links in the column headers to sort by the different quanitities.

The values are plotted so that the minimum and maximum
are marked at the end of the whiskers, the mean value is shown with a
horizontal tick across each box, and the boxes show the range of plus
and minus one standard deviation from the mean value. The average temperature
is shown with a dashed horizontal line and the average extremes are drawn with
dotted lines.